What is the center and radius of the​ circle?

A circle is a set of points equidistant from a center point. Here's a set of points equidistant from the origin! A common form to write the equation of a circle in is the center-radius form. The center-radius form is: (x−h)2+(y−k)2=r2 Here, the center point is denoted by (h,k) and r is the radius of the circle.

Volume = the base times the height. i’m not going your work for you, but this is all you need to know.